From the 20th Century to the 21st Century and Beyond
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Since its first flight in 1981, the Space Shuttle has undergone a continuous evolution to remain the safest, most reliable and capable space launch vehicle in the world. Some of the key improvements made to the Space Shuttle fleet include an increased cargo capacity of eight tons, a lighter fuel tank, a major redesign of the solid rockets, changes to the Space Shuttle main engines, the addition of a crew escape and bailout system, a stronger landing gear, more powerful flight control computers, and updated inertial navigation equipment to name a few.
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These improvements have increased safety and reduced the estimated risks during launch by more than 80 percent. They have decreased the number of actual problems experienced in flight by 70 percent, and decreased the annual cost of operating the Shuttle by 40 percent.
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In the 21st Century, the Space Shuttle fleet will continue to undergo significant improvements. Shuttle systems that will be the object of upgrades include the main engines, solid rocket boosters, external tank, auxiliary power units, fuel cells, avionics, mass memory units, main landing gear, and vital orbiter surfaces. These and other continuing improvements will keep the Shuttle flying safely and reliably for another decade and beyond.
